Neurological stimulation leads refer to medical leads used to stimulate a patient's nervous system. Examples of neurological stimulation leads include spinal cord stimulation leads, deep brain stimulation leads and the like. For example, deep brain stimulation leads can be implanted at a precise location within the brain using stereotactic guidance and computed tomography (CT) or magnetic resonance imaging (MRI) techniques. Once implanted, the lead can deliver electrical stimulation to the brain in order to induce nerve impulses that inhibit symptoms of the brain disorder.
Deep brain stimulation systems typically include a pulse generator operatively connected to the implanted lead. Electrical pulses are delivered to the brain by an electrode disposed on a distal end of the implanted lead. Deep brain stimulation has been used to relieve chronic pain of neuropathic or nociceptive origin. Deep brain stimulation has also been used to treat movement disorders, such as Parkinsons Disease, as well as epilepsy and psychiatric disorders. After implanting a neurological lead, the implanted lead is often connected to a neurological lead extension, which in turn couples to the pulse generator that generates and delivers electrical pulses to a patient via the lead.
Percutaneous neurological extensions are often used immediately following implantation of a neurological lead. A percutaneous neurological extension generally refers to a temporary, non-permanent extension. Such percutaneous neurological extensions are typically used only when the patient is in the hospital under physician supervision, during which the percutaneous neurological extension may be attached to a screening cable for electrical connection to an external neurological device such as an external pulse generator or an external screener. A permanent neurological extension can replace the percutaneous neurological extension once proper operation of deep brain stimulation system has been demonstrated and verified on the patient with the temporary external system. The permanent neurological extension can be coupled to another neurological device, such as an implanted pulse generator.
Most percutaneous neurological extensions include a channel for receiving the neurological lead. Electrical contact between the extension and the lead is made in the channel. Set screws are typically inserted and/or tightened by a physician into the percutaneous neurological extension to ensure a good electrical connection between the lead and the extension and also to ensure that the lead does not dislodge from the channel of the extension.